We know (√(x−1)−2)-(√(x−1)−3) = 1
so let (√(x−1)−2 = t
so let (√(x−1)−2 = t
|t | + |t -1 | = 1
t cannot be < 0 then t-1 is less than -1
and |t | + |t -1 | > 1
t cannot be > 1 then t-1 is less than -1
and |t | + |t -1 | > 1
so we need to check 0 < = t < = 1
if t = 1 then |t | + |t -1 | = 1
if t = 0 then |t | + |t -1 | = 1
if 0 < t < 1 then t-1 < 0 so |t | +
|t -1 | = t + 1- t = 1
so 0 < = t < = 1
or 0
<= √(x−1)−2
<= 1
or 2 < = √(x−1) or <= 3
5 < = x <= 10
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